OTTAWA — Federal officials have yet to figure out how to make good on the Trudeau government's 18-month-old promise to provide up to 150 police officers to peacekeeping missions, despite a shortage of such personnel on many UN operations.

The Liberals first pledged the police officers in August 2016 at the same time they said that Canada would contribute up to 600 soldiers to UN missions as part of a renewed commitment to peacekeeping.

The government has since put meat on its promise of troops by committing military helicopters, aircraft, trainers and a rapid-reaction force, with talks between National Defence and the United Nations about possible missions underway.

But Public Safety Canada spokeswoman Karine Martel told The Canadian Press that the government "continues to explore options to increase police officer deployments up to 150." She did not provide a timeline for a decision.

In the meantime, the number of Canadian police officers deployed on UN missions has plummeted in the 18 months since the Liberals made their pledge; 20 were in the field — all in Haiti — at the end of January, compared to 84 in August 2016.

The shrinking contributions and lack of a plan has several peacekeeping experts scratching their heads, as the UN has been asking the international community to contribute more police officers.

A quick glance at the peacekeeping missions in Mali and South Sudan, for example, show those missions are missing hundreds of police, which are considered essential for building long-term peace and stability in countries.

"Many missions are desperate for police," said Walter Dorn, an expert on peacekeeping at the Canadian Forces College in Toronto. "There's a big need."

In addition to those in Haiti, there were 26 other Canadian police officers assigned to non-UN missions at the end of January, including 18 in Ukraine, five in Iraq and three in the West Bank.

The government has indicated that it is counting those officers against its commitment, which Jocelyn Coulon, who was an adviser to former foreign affairs minister Stephane Dion, said does not meet the spirit of the pledge.

"My understanding was 150 in peace operations," said Coulon, who is now director of the Francophone Network on Peace Operations at the University of Montreal.

"Ukraine is not a peace operation. And I don't think Iraq is also a peace operation. Peace operations are usually authorized by the Security Council, either under the UN flag or non-UN flag like the African Union or European Union."

The UN underscored the need for more police in the lead-up to November's peacekeeping summit in Vancouver, stating: "The growing importance of UN police needs to be matched with appropriate adequately resourced capabilities."

But while Canada pledged to make transport and attack helicopters, a transport aircraft, a 200-strong rapid-response team and dozens of trainers available for peacekeeping, there was little mention of police officers.

Coulon said the question is why.

"Is it a funding question or a political-willingness question? I don't know."